Principal Proposed Uses

Other Proposed Uses

Citrus aurantium
is the Latin name for a fruit called Seville orange, or bitter orange. The juice, peel, and essential oil have all been used medicinally. Traditionally uses include digestive problems, epilepsy, fatigue, insomnia, infections, respiratory problems, skin problems, and many other uses. As a flavoring, essence of bitter orange is found in the drinks Triple Sec and Cointreau.

What is

Citrus aurantium
juice and peel contain the stimulant chemical synephrine as well as related stimulants such as octopamine, tyramine, N-methyltyramine, and hordeline. On this basis,
Citrus aurantium
has been widely marketed as a
weight-loss product
. However, there is no reliable evidence that
Citrus aurantium
is effective, and considerable reason to worry that it may cause harm (see
Safety Issues
). The reassuring statement made by some manufacturers that
Citrus aurantium
offers the “benefits of ephedra without the risks” is not supported by scientific evidence.

The only published
double-blind, placebo-controlled trial
on
Citrus aurantium
juice did not test the herb alone, but rather evaluated a combination product that also contained caffeine and
St. John's wort
.
1
While the results were somewhat positive, overall the study was too preliminary to reach reliable conclusions. An even less reliable study evaluated the synephrine constituent of
Citrus aurantium
and found possible “fat burning” actions.
2
In view of the weakness of the evidence in favor of
Citrus aurantium
, and the considerable evidence that it presents health risks, we recommend against using it for weight loss.

The
essential oil
of
Citrus aurantium
contains linalool and the fragrant substance limonene and might have antianxiety and sedative effects.
8
However, neither of these proposed uses has more than extremely preliminary supporting evidence.

Dosage

Many
Citrus aurantium
products are made from the juice and/or concentrated extracts of the peel and are said to contain a fixed percentage of synephrine or total amines. A typical recommended dosage of such products ranges from 100–150 mg two to three times daily. However, these doses may be unsafe.

Safety Issues

Most of the safety concerns regarding citrus aurantium relate to its stimulant constituents.

The drug synephrine is known to produce many unpleasant and possibly dangerous side effects, including headache, agitation, rapid heart rate, and heart palpitations. In some people, it can cause
angina pectoris
, kidney damage, increased pressure in the eye, and reduced blood circulation to the heart and the extremities. The other stimulant amines in
Citrus aurantium
may increase such effects. There is one case report of a heart attack that appears possibly related to use of a citrus aurantium supplement,
9
and another that links the herb to stroke.
14Citrus aurantium
juice or concentrated extracts can raise blood pressure and increase heart rate
15
and therefore should not be used by individuals with
cardiovascular disease
or
high blood pressure
. The herb should also be avoided by people with
glaucoma
.

Synephrine can also interact with numerous medications and other drugs, including stimulants (e.g.,
ephedrine
, pseudoephedrine (Sudafed), Ritalin, and even caffeine) and anesthetics. The tyramine constituent of
Citrus aurantium
can cause deadly side effects when combined with drugs in the
MAO inhibitor
family.

The peel and essential oil of
Citrus aurantium
may cause photosensitivity (increased tendency to react to sun exposure). For this reason, combination treatment with drugs that cause the same side effect (such as
sulfa antibiotics
) is not recommended.

Finally,
Citrus aurantium
juice can alter the way that the liver processes various medications, potentially raising or lowering their levels.
10-13

In particular, the drugs
cyclosporine
and felodipine (a
calcium channel blocker
) are thought to be affected by
Citrus aurantium
juice, but numerous other drugs may interact with it as well. For this reason, we recommend that if you are taking any medication that is critical to your health, you should not take
Citrus aurantium
juice.

Safety in young children, pregnant or nursing women, or people with severe liver or kidney disease has not been established.

Interactions You Should Know About

If you are taking

Drugs in the
MAO inhibitor
family: Do not use
Citrus aurantium
at all.

Ephedrine, pseudoephedrine (Sudafed), Ritalin,
cyclosporine
,
calcium channel blockers, drugs that cause photosensitivity (such as
sulfa antibiotics
), or any medication that is critical to your health: Do not use
Citrus aurantium
without consulting a physician.

Revision Information

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.